All parameters are now transferred to the drive.
A separate manual for MCT 10 Set-up Software, MG.
10.RX.YY, is available.
8.8.1 High Voltage Test
Carry out a high voltage test by short-circuiting terminals
U, V, W, L
1
, L
2
and L
3
. Energize maximum 2.15 kV DC for
380-500V frequency converters and 2.525 kV DC for
525-690V frequency converters for one second between
this short-circuit and the chassis.
WARNING
When running high voltage tests of the entire installation,
interrupt the mains and motor connection if the leakage
currents are too high.
8.8.2 Earthing
The following basic issues need to be considered when
installing a frequency converter, so as to obtain electro-
magnetic compatibility (EMC).
•
Safety earthing: Please note that the frequency
converter has a high leakage current and must be
earthed appropriately for safety reasons. Apply
local safety regulations.
•
High-frequency earthing: Keep the earth wire
connections as short as possible.
Connect the different earth systems at the lowest possible
conductor impedance. The lowest possible conductor
impedance is obtained by keeping the conductor as short
as possible and by using the greatest possible surface area.
The metal cabinets of the different devices are mounted
on the cabinet rear plate using the lowest possible HF
impedance. This avoids having different HF voltages for
the individual devices and avoids the risk of radio
interference currents running in connection cables that
may be used between the devices. The radio interference
will have been reduced.
In order to obtain a low HF impedance, use the fastening
bolts of the devices as HF connection to the rear plate. It is
necessary to remove insulating paint or similar from the
fastening points.
8.8.3 Safety Earth Connection
The frequency converter has a high leakage current and
must be earthed appropriately for safety reasons according
to EN 50178.
WARNING
The earth leakage current from the frequency converter
exceeds 3.5 mA. To ensure a good mechanical connection
from the earth cable to the earth connection (terminal 95),
the cable cross-section must be at least 10 mm
2
or 2 rated
earth wires terminated separately.
8.9 EMC-correct Installation
8.9.1 Electrical Installation - EMC
Precautions
The following is a guideline to good engineering practice
when installing frequency converters. Follow these
guidelines to comply with EN 61800-3
First environment
. If
the installation is in EN 61800-3
Second environment,
i.e.
industrial networks, or in an installation with its own
transformer, deviation from these guidelines is allowed but
not recommended. See also paragraphs
CE Labelling,
General Aspects of EMC Emission
and
EMC Test Results
.
Good engineering practice to ensure EMC-correct
electrical installation:
•
Use only braided screened/armoured motor
cables and braided screened/armoured control
cables. The screen should provide a minimum
coverage of 80%. The screen material must be
metal, not limited to but typically copper,
aluminium, steel or lead. There are no special
requirements for the mains cable.
•
Installations using rigid metal conduits are not
required to use screened cable, but the motor
cable must be installed in conduit separate from
the control and mains cables. Full connection of
the conduit from the drive to the motor is
required. The EMC performance of flexible
conduits varies a lot and information from the
manufacturer must be obtained.
•
Connect the screen/armour/conduit to earth at
both ends for motor cables as well as for control
cables. In some cases, it is not possible to
connect the screen in both ends. If so, connect
the screen at the frequency converter. See also
Earthing of Braided Screened/Armoured Control
Cables
.
•
Avoid terminating the screen/armour with twisted
ends (pigtails). It increases the high frequency
impedance of the screen, which reduces its
effectiveness at high frequencies. Use low
impedance cable clamps or EMC cable glands
instead.
•
Avoid using unscreened/unarmoured motor or
control cables inside cabinets housing the
drive(s), whenever this can be avoided.
Electrical Installation
FC 300 Design Guide
220
MG.33.BD.02 - VLT
®
is a registered Danfoss trademark
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